Commit | Line | Data |
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85f2b082 TZ |
1 | /* |
2 | * trace_events_trigger - trace event triggers | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License as published by | |
6 | * the Free Software Foundation; either version 2 of the License, or | |
7 | * (at your option) any later version. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License | |
15 | * along with this program; if not, write to the Free Software | |
16 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
17 | * | |
18 | * Copyright (C) 2013 Tom Zanussi <tom.zanussi@linux.intel.com> | |
19 | */ | |
20 | ||
21 | #include <linux/module.h> | |
22 | #include <linux/ctype.h> | |
23 | #include <linux/mutex.h> | |
24 | #include <linux/slab.h> | |
25 | ||
26 | #include "trace.h" | |
27 | ||
28 | static LIST_HEAD(trigger_commands); | |
29 | static DEFINE_MUTEX(trigger_cmd_mutex); | |
30 | ||
ab4bf008 | 31 | void trigger_data_free(struct event_trigger_data *data) |
2a2df321 | 32 | { |
bac5fb97 TZ |
33 | if (data->cmd_ops->set_filter) |
34 | data->cmd_ops->set_filter(NULL, data, NULL); | |
35 | ||
2a2df321 TZ |
36 | synchronize_sched(); /* make sure current triggers exit before free */ |
37 | kfree(data); | |
38 | } | |
39 | ||
85f2b082 TZ |
40 | /** |
41 | * event_triggers_call - Call triggers associated with a trace event | |
7f1d2f82 | 42 | * @file: The trace_event_file associated with the event |
bac5fb97 | 43 | * @rec: The trace entry for the event, NULL for unconditional invocation |
85f2b082 TZ |
44 | * |
45 | * For each trigger associated with an event, invoke the trigger | |
bac5fb97 TZ |
46 | * function registered with the associated trigger command. If rec is |
47 | * non-NULL, it means that the trigger requires further processing and | |
48 | * shouldn't be unconditionally invoked. If rec is non-NULL and the | |
49 | * trigger has a filter associated with it, rec will checked against | |
50 | * the filter and if the record matches the trigger will be invoked. | |
51 | * If the trigger is a 'post_trigger', meaning it shouldn't be invoked | |
52 | * in any case until the current event is written, the trigger | |
53 | * function isn't invoked but the bit associated with the deferred | |
54 | * trigger is set in the return value. | |
55 | * | |
56 | * Returns an enum event_trigger_type value containing a set bit for | |
57 | * any trigger that should be deferred, ETT_NONE if nothing to defer. | |
85f2b082 TZ |
58 | * |
59 | * Called from tracepoint handlers (with rcu_read_lock_sched() held). | |
60 | * | |
61 | * Return: an enum event_trigger_type value containing a set bit for | |
62 | * any trigger that should be deferred, ETT_NONE if nothing to defer. | |
63 | */ | |
bac5fb97 | 64 | enum event_trigger_type |
7f1d2f82 | 65 | event_triggers_call(struct trace_event_file *file, void *rec) |
85f2b082 TZ |
66 | { |
67 | struct event_trigger_data *data; | |
bac5fb97 | 68 | enum event_trigger_type tt = ETT_NONE; |
d8a30f20 | 69 | struct event_filter *filter; |
85f2b082 TZ |
70 | |
71 | if (list_empty(&file->triggers)) | |
bac5fb97 | 72 | return tt; |
85f2b082 | 73 | |
bac5fb97 | 74 | list_for_each_entry_rcu(data, &file->triggers, list) { |
104f2810 TZ |
75 | if (data->paused) |
76 | continue; | |
bac5fb97 | 77 | if (!rec) { |
c4a59230 | 78 | data->ops->func(data, rec); |
bac5fb97 TZ |
79 | continue; |
80 | } | |
561a4fe8 | 81 | filter = rcu_dereference_sched(data->filter); |
d8a30f20 | 82 | if (filter && !filter_match_preds(filter, rec)) |
bac5fb97 | 83 | continue; |
353206f5 | 84 | if (event_command_post_trigger(data->cmd_ops)) { |
bac5fb97 TZ |
85 | tt |= data->cmd_ops->trigger_type; |
86 | continue; | |
87 | } | |
c4a59230 | 88 | data->ops->func(data, rec); |
bac5fb97 TZ |
89 | } |
90 | return tt; | |
85f2b082 TZ |
91 | } |
92 | EXPORT_SYMBOL_GPL(event_triggers_call); | |
93 | ||
bac5fb97 TZ |
94 | /** |
95 | * event_triggers_post_call - Call 'post_triggers' for a trace event | |
7f1d2f82 | 96 | * @file: The trace_event_file associated with the event |
bac5fb97 | 97 | * @tt: enum event_trigger_type containing a set bit for each trigger to invoke |
c4a59230 | 98 | * @rec: The trace entry for the event |
bac5fb97 TZ |
99 | * |
100 | * For each trigger associated with an event, invoke the trigger | |
101 | * function registered with the associated trigger command, if the | |
102 | * corresponding bit is set in the tt enum passed into this function. | |
103 | * See @event_triggers_call for details on how those bits are set. | |
104 | * | |
105 | * Called from tracepoint handlers (with rcu_read_lock_sched() held). | |
106 | */ | |
107 | void | |
7f1d2f82 | 108 | event_triggers_post_call(struct trace_event_file *file, |
c4a59230 TZ |
109 | enum event_trigger_type tt, |
110 | void *rec) | |
bac5fb97 TZ |
111 | { |
112 | struct event_trigger_data *data; | |
113 | ||
114 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
104f2810 TZ |
115 | if (data->paused) |
116 | continue; | |
bac5fb97 | 117 | if (data->cmd_ops->trigger_type & tt) |
c4a59230 | 118 | data->ops->func(data, rec); |
bac5fb97 TZ |
119 | } |
120 | } | |
121 | EXPORT_SYMBOL_GPL(event_triggers_post_call); | |
122 | ||
dd97b954 SRRH |
123 | #define SHOW_AVAILABLE_TRIGGERS (void *)(1UL) |
124 | ||
85f2b082 TZ |
125 | static void *trigger_next(struct seq_file *m, void *t, loff_t *pos) |
126 | { | |
7f1d2f82 | 127 | struct trace_event_file *event_file = event_file_data(m->private); |
85f2b082 | 128 | |
dd97b954 SRRH |
129 | if (t == SHOW_AVAILABLE_TRIGGERS) |
130 | return NULL; | |
131 | ||
85f2b082 TZ |
132 | return seq_list_next(t, &event_file->triggers, pos); |
133 | } | |
134 | ||
135 | static void *trigger_start(struct seq_file *m, loff_t *pos) | |
136 | { | |
7f1d2f82 | 137 | struct trace_event_file *event_file; |
85f2b082 TZ |
138 | |
139 | /* ->stop() is called even if ->start() fails */ | |
140 | mutex_lock(&event_mutex); | |
141 | event_file = event_file_data(m->private); | |
142 | if (unlikely(!event_file)) | |
143 | return ERR_PTR(-ENODEV); | |
144 | ||
dd97b954 SRRH |
145 | if (list_empty(&event_file->triggers)) |
146 | return *pos == 0 ? SHOW_AVAILABLE_TRIGGERS : NULL; | |
147 | ||
85f2b082 TZ |
148 | return seq_list_start(&event_file->triggers, *pos); |
149 | } | |
150 | ||
151 | static void trigger_stop(struct seq_file *m, void *t) | |
152 | { | |
153 | mutex_unlock(&event_mutex); | |
154 | } | |
155 | ||
156 | static int trigger_show(struct seq_file *m, void *v) | |
157 | { | |
158 | struct event_trigger_data *data; | |
dd97b954 SRRH |
159 | struct event_command *p; |
160 | ||
161 | if (v == SHOW_AVAILABLE_TRIGGERS) { | |
162 | seq_puts(m, "# Available triggers:\n"); | |
163 | seq_putc(m, '#'); | |
164 | mutex_lock(&trigger_cmd_mutex); | |
165 | list_for_each_entry_reverse(p, &trigger_commands, list) | |
166 | seq_printf(m, " %s", p->name); | |
167 | seq_putc(m, '\n'); | |
168 | mutex_unlock(&trigger_cmd_mutex); | |
169 | return 0; | |
170 | } | |
85f2b082 TZ |
171 | |
172 | data = list_entry(v, struct event_trigger_data, list); | |
173 | data->ops->print(m, data->ops, data); | |
174 | ||
175 | return 0; | |
176 | } | |
177 | ||
178 | static const struct seq_operations event_triggers_seq_ops = { | |
179 | .start = trigger_start, | |
180 | .next = trigger_next, | |
181 | .stop = trigger_stop, | |
182 | .show = trigger_show, | |
183 | }; | |
184 | ||
185 | static int event_trigger_regex_open(struct inode *inode, struct file *file) | |
186 | { | |
187 | int ret = 0; | |
188 | ||
189 | mutex_lock(&event_mutex); | |
190 | ||
191 | if (unlikely(!event_file_data(file))) { | |
192 | mutex_unlock(&event_mutex); | |
193 | return -ENODEV; | |
194 | } | |
195 | ||
a88e1cfb TZ |
196 | if ((file->f_mode & FMODE_WRITE) && |
197 | (file->f_flags & O_TRUNC)) { | |
198 | struct trace_event_file *event_file; | |
199 | struct event_command *p; | |
200 | ||
201 | event_file = event_file_data(file); | |
202 | ||
203 | list_for_each_entry(p, &trigger_commands, list) { | |
204 | if (p->unreg_all) | |
205 | p->unreg_all(event_file); | |
206 | } | |
207 | } | |
208 | ||
85f2b082 TZ |
209 | if (file->f_mode & FMODE_READ) { |
210 | ret = seq_open(file, &event_triggers_seq_ops); | |
211 | if (!ret) { | |
212 | struct seq_file *m = file->private_data; | |
213 | m->private = file; | |
214 | } | |
215 | } | |
216 | ||
217 | mutex_unlock(&event_mutex); | |
218 | ||
219 | return ret; | |
220 | } | |
221 | ||
7f1d2f82 | 222 | static int trigger_process_regex(struct trace_event_file *file, char *buff) |
85f2b082 TZ |
223 | { |
224 | char *command, *next = buff; | |
225 | struct event_command *p; | |
226 | int ret = -EINVAL; | |
227 | ||
228 | command = strsep(&next, ": \t"); | |
229 | command = (command[0] != '!') ? command : command + 1; | |
230 | ||
231 | mutex_lock(&trigger_cmd_mutex); | |
232 | list_for_each_entry(p, &trigger_commands, list) { | |
233 | if (strcmp(p->name, command) == 0) { | |
234 | ret = p->func(p, file, buff, command, next); | |
235 | goto out_unlock; | |
236 | } | |
237 | } | |
238 | out_unlock: | |
239 | mutex_unlock(&trigger_cmd_mutex); | |
240 | ||
241 | return ret; | |
242 | } | |
243 | ||
244 | static ssize_t event_trigger_regex_write(struct file *file, | |
245 | const char __user *ubuf, | |
246 | size_t cnt, loff_t *ppos) | |
247 | { | |
7f1d2f82 | 248 | struct trace_event_file *event_file; |
85f2b082 TZ |
249 | ssize_t ret; |
250 | char *buf; | |
251 | ||
252 | if (!cnt) | |
253 | return 0; | |
254 | ||
255 | if (cnt >= PAGE_SIZE) | |
256 | return -EINVAL; | |
257 | ||
70f6cbb6 AV |
258 | buf = memdup_user_nul(ubuf, cnt); |
259 | if (IS_ERR(buf)) | |
260 | return PTR_ERR(buf); | |
85f2b082 | 261 | |
85f2b082 TZ |
262 | strim(buf); |
263 | ||
264 | mutex_lock(&event_mutex); | |
265 | event_file = event_file_data(file); | |
266 | if (unlikely(!event_file)) { | |
267 | mutex_unlock(&event_mutex); | |
70f6cbb6 | 268 | kfree(buf); |
85f2b082 TZ |
269 | return -ENODEV; |
270 | } | |
271 | ret = trigger_process_regex(event_file, buf); | |
272 | mutex_unlock(&event_mutex); | |
273 | ||
70f6cbb6 | 274 | kfree(buf); |
85f2b082 TZ |
275 | if (ret < 0) |
276 | goto out; | |
277 | ||
278 | *ppos += cnt; | |
279 | ret = cnt; | |
280 | out: | |
281 | return ret; | |
282 | } | |
283 | ||
284 | static int event_trigger_regex_release(struct inode *inode, struct file *file) | |
285 | { | |
286 | mutex_lock(&event_mutex); | |
287 | ||
288 | if (file->f_mode & FMODE_READ) | |
289 | seq_release(inode, file); | |
290 | ||
291 | mutex_unlock(&event_mutex); | |
292 | ||
293 | return 0; | |
294 | } | |
295 | ||
296 | static ssize_t | |
297 | event_trigger_write(struct file *filp, const char __user *ubuf, | |
298 | size_t cnt, loff_t *ppos) | |
299 | { | |
300 | return event_trigger_regex_write(filp, ubuf, cnt, ppos); | |
301 | } | |
302 | ||
303 | static int | |
304 | event_trigger_open(struct inode *inode, struct file *filp) | |
305 | { | |
306 | return event_trigger_regex_open(inode, filp); | |
307 | } | |
308 | ||
309 | static int | |
310 | event_trigger_release(struct inode *inode, struct file *file) | |
311 | { | |
312 | return event_trigger_regex_release(inode, file); | |
313 | } | |
314 | ||
315 | const struct file_operations event_trigger_fops = { | |
316 | .open = event_trigger_open, | |
317 | .read = seq_read, | |
318 | .write = event_trigger_write, | |
098c879e | 319 | .llseek = tracing_lseek, |
85f2b082 TZ |
320 | .release = event_trigger_release, |
321 | }; | |
322 | ||
2a2df321 TZ |
323 | /* |
324 | * Currently we only register event commands from __init, so mark this | |
325 | * __init too. | |
326 | */ | |
ab4bf008 | 327 | __init int register_event_command(struct event_command *cmd) |
2a2df321 TZ |
328 | { |
329 | struct event_command *p; | |
330 | int ret = 0; | |
331 | ||
332 | mutex_lock(&trigger_cmd_mutex); | |
333 | list_for_each_entry(p, &trigger_commands, list) { | |
334 | if (strcmp(cmd->name, p->name) == 0) { | |
335 | ret = -EBUSY; | |
336 | goto out_unlock; | |
337 | } | |
338 | } | |
339 | list_add(&cmd->list, &trigger_commands); | |
340 | out_unlock: | |
341 | mutex_unlock(&trigger_cmd_mutex); | |
342 | ||
343 | return ret; | |
344 | } | |
345 | ||
346 | /* | |
347 | * Currently we only unregister event commands from __init, so mark | |
348 | * this __init too. | |
349 | */ | |
d0bad49b | 350 | __init int unregister_event_command(struct event_command *cmd) |
2a2df321 TZ |
351 | { |
352 | struct event_command *p, *n; | |
353 | int ret = -ENODEV; | |
354 | ||
355 | mutex_lock(&trigger_cmd_mutex); | |
356 | list_for_each_entry_safe(p, n, &trigger_commands, list) { | |
357 | if (strcmp(cmd->name, p->name) == 0) { | |
358 | ret = 0; | |
359 | list_del_init(&p->list); | |
360 | goto out_unlock; | |
361 | } | |
362 | } | |
363 | out_unlock: | |
364 | mutex_unlock(&trigger_cmd_mutex); | |
365 | ||
366 | return ret; | |
367 | } | |
368 | ||
369 | /** | |
370 | * event_trigger_print - Generic event_trigger_ops @print implementation | |
371 | * @name: The name of the event trigger | |
372 | * @m: The seq_file being printed to | |
373 | * @data: Trigger-specific data | |
374 | * @filter_str: filter_str to print, if present | |
375 | * | |
376 | * Common implementation for event triggers to print themselves. | |
377 | * | |
378 | * Usually wrapped by a function that simply sets the @name of the | |
379 | * trigger command and then invokes this. | |
380 | * | |
381 | * Return: 0 on success, errno otherwise | |
382 | */ | |
383 | static int | |
384 | event_trigger_print(const char *name, struct seq_file *m, | |
385 | void *data, char *filter_str) | |
386 | { | |
387 | long count = (long)data; | |
388 | ||
fa6f0cc7 | 389 | seq_puts(m, name); |
2a2df321 TZ |
390 | |
391 | if (count == -1) | |
392 | seq_puts(m, ":unlimited"); | |
393 | else | |
394 | seq_printf(m, ":count=%ld", count); | |
395 | ||
396 | if (filter_str) | |
397 | seq_printf(m, " if %s\n", filter_str); | |
398 | else | |
1177e436 | 399 | seq_putc(m, '\n'); |
2a2df321 TZ |
400 | |
401 | return 0; | |
402 | } | |
403 | ||
404 | /** | |
405 | * event_trigger_init - Generic event_trigger_ops @init implementation | |
406 | * @ops: The trigger ops associated with the trigger | |
407 | * @data: Trigger-specific data | |
408 | * | |
409 | * Common implementation of event trigger initialization. | |
410 | * | |
411 | * Usually used directly as the @init method in event trigger | |
412 | * implementations. | |
413 | * | |
414 | * Return: 0 on success, errno otherwise | |
415 | */ | |
ab4bf008 TZ |
416 | int event_trigger_init(struct event_trigger_ops *ops, |
417 | struct event_trigger_data *data) | |
2a2df321 TZ |
418 | { |
419 | data->ref++; | |
420 | return 0; | |
421 | } | |
422 | ||
423 | /** | |
424 | * event_trigger_free - Generic event_trigger_ops @free implementation | |
425 | * @ops: The trigger ops associated with the trigger | |
426 | * @data: Trigger-specific data | |
427 | * | |
428 | * Common implementation of event trigger de-initialization. | |
429 | * | |
430 | * Usually used directly as the @free method in event trigger | |
431 | * implementations. | |
432 | */ | |
433 | static void | |
434 | event_trigger_free(struct event_trigger_ops *ops, | |
435 | struct event_trigger_data *data) | |
436 | { | |
437 | if (WARN_ON_ONCE(data->ref <= 0)) | |
438 | return; | |
439 | ||
440 | data->ref--; | |
441 | if (!data->ref) | |
442 | trigger_data_free(data); | |
443 | } | |
444 | ||
ab4bf008 TZ |
445 | int trace_event_trigger_enable_disable(struct trace_event_file *file, |
446 | int trigger_enable) | |
85f2b082 TZ |
447 | { |
448 | int ret = 0; | |
449 | ||
450 | if (trigger_enable) { | |
451 | if (atomic_inc_return(&file->tm_ref) > 1) | |
452 | return ret; | |
5d6ad960 | 453 | set_bit(EVENT_FILE_FL_TRIGGER_MODE_BIT, &file->flags); |
85f2b082 TZ |
454 | ret = trace_event_enable_disable(file, 1, 1); |
455 | } else { | |
456 | if (atomic_dec_return(&file->tm_ref) > 0) | |
457 | return ret; | |
5d6ad960 | 458 | clear_bit(EVENT_FILE_FL_TRIGGER_MODE_BIT, &file->flags); |
85f2b082 TZ |
459 | ret = trace_event_enable_disable(file, 0, 1); |
460 | } | |
461 | ||
462 | return ret; | |
463 | } | |
464 | ||
465 | /** | |
466 | * clear_event_triggers - Clear all triggers associated with a trace array | |
467 | * @tr: The trace array to clear | |
468 | * | |
469 | * For each trigger, the triggering event has its tm_ref decremented | |
470 | * via trace_event_trigger_enable_disable(), and any associated event | |
471 | * (in the case of enable/disable_event triggers) will have its sm_ref | |
472 | * decremented via free()->trace_event_enable_disable(). That | |
473 | * combination effectively reverses the soft-mode/trigger state added | |
474 | * by trigger registration. | |
475 | * | |
476 | * Must be called with event_mutex held. | |
477 | */ | |
478 | void | |
479 | clear_event_triggers(struct trace_array *tr) | |
480 | { | |
7f1d2f82 | 481 | struct trace_event_file *file; |
85f2b082 TZ |
482 | |
483 | list_for_each_entry(file, &tr->events, list) { | |
484 | struct event_trigger_data *data; | |
485 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
486 | trace_event_trigger_enable_disable(file, 0); | |
487 | if (data->ops->free) | |
488 | data->ops->free(data->ops, data); | |
489 | } | |
490 | } | |
491 | } | |
492 | ||
bac5fb97 TZ |
493 | /** |
494 | * update_cond_flag - Set or reset the TRIGGER_COND bit | |
7f1d2f82 | 495 | * @file: The trace_event_file associated with the event |
bac5fb97 TZ |
496 | * |
497 | * If an event has triggers and any of those triggers has a filter or | |
498 | * a post_trigger, trigger invocation needs to be deferred until after | |
499 | * the current event has logged its data, and the event should have | |
500 | * its TRIGGER_COND bit set, otherwise the TRIGGER_COND bit should be | |
501 | * cleared. | |
502 | */ | |
ab4bf008 | 503 | void update_cond_flag(struct trace_event_file *file) |
bac5fb97 TZ |
504 | { |
505 | struct event_trigger_data *data; | |
506 | bool set_cond = false; | |
507 | ||
508 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
353206f5 SRRH |
509 | if (data->filter || event_command_post_trigger(data->cmd_ops) || |
510 | event_command_needs_rec(data->cmd_ops)) { | |
bac5fb97 TZ |
511 | set_cond = true; |
512 | break; | |
513 | } | |
514 | } | |
515 | ||
516 | if (set_cond) | |
5d6ad960 | 517 | set_bit(EVENT_FILE_FL_TRIGGER_COND_BIT, &file->flags); |
bac5fb97 | 518 | else |
5d6ad960 | 519 | clear_bit(EVENT_FILE_FL_TRIGGER_COND_BIT, &file->flags); |
bac5fb97 TZ |
520 | } |
521 | ||
2a2df321 TZ |
522 | /** |
523 | * register_trigger - Generic event_command @reg implementation | |
524 | * @glob: The raw string used to register the trigger | |
525 | * @ops: The trigger ops associated with the trigger | |
526 | * @data: Trigger-specific data to associate with the trigger | |
7f1d2f82 | 527 | * @file: The trace_event_file associated with the event |
2a2df321 TZ |
528 | * |
529 | * Common implementation for event trigger registration. | |
530 | * | |
531 | * Usually used directly as the @reg method in event command | |
532 | * implementations. | |
533 | * | |
534 | * Return: 0 on success, errno otherwise | |
535 | */ | |
536 | static int register_trigger(char *glob, struct event_trigger_ops *ops, | |
537 | struct event_trigger_data *data, | |
7f1d2f82 | 538 | struct trace_event_file *file) |
2a2df321 TZ |
539 | { |
540 | struct event_trigger_data *test; | |
541 | int ret = 0; | |
542 | ||
543 | list_for_each_entry_rcu(test, &file->triggers, list) { | |
544 | if (test->cmd_ops->trigger_type == data->cmd_ops->trigger_type) { | |
545 | ret = -EEXIST; | |
546 | goto out; | |
547 | } | |
548 | } | |
549 | ||
550 | if (data->ops->init) { | |
551 | ret = data->ops->init(data->ops, data); | |
552 | if (ret < 0) | |
553 | goto out; | |
554 | } | |
555 | ||
556 | list_add_rcu(&data->list, &file->triggers); | |
557 | ret++; | |
558 | ||
4e4a4d75 | 559 | update_cond_flag(file); |
2a2df321 TZ |
560 | if (trace_event_trigger_enable_disable(file, 1) < 0) { |
561 | list_del_rcu(&data->list); | |
4e4a4d75 | 562 | update_cond_flag(file); |
2a2df321 TZ |
563 | ret--; |
564 | } | |
565 | out: | |
566 | return ret; | |
567 | } | |
568 | ||
569 | /** | |
570 | * unregister_trigger - Generic event_command @unreg implementation | |
571 | * @glob: The raw string used to register the trigger | |
572 | * @ops: The trigger ops associated with the trigger | |
573 | * @test: Trigger-specific data used to find the trigger to remove | |
7f1d2f82 | 574 | * @file: The trace_event_file associated with the event |
2a2df321 TZ |
575 | * |
576 | * Common implementation for event trigger unregistration. | |
577 | * | |
578 | * Usually used directly as the @unreg method in event command | |
579 | * implementations. | |
580 | */ | |
ab4bf008 TZ |
581 | void unregister_trigger(char *glob, struct event_trigger_ops *ops, |
582 | struct event_trigger_data *test, | |
583 | struct trace_event_file *file) | |
2a2df321 TZ |
584 | { |
585 | struct event_trigger_data *data; | |
586 | bool unregistered = false; | |
587 | ||
588 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
589 | if (data->cmd_ops->trigger_type == test->cmd_ops->trigger_type) { | |
590 | unregistered = true; | |
591 | list_del_rcu(&data->list); | |
592 | trace_event_trigger_enable_disable(file, 0); | |
4e4a4d75 | 593 | update_cond_flag(file); |
2a2df321 TZ |
594 | break; |
595 | } | |
596 | } | |
597 | ||
598 | if (unregistered && data->ops->free) | |
599 | data->ops->free(data->ops, data); | |
600 | } | |
601 | ||
602 | /** | |
603 | * event_trigger_callback - Generic event_command @func implementation | |
604 | * @cmd_ops: The command ops, used for trigger registration | |
7f1d2f82 | 605 | * @file: The trace_event_file associated with the event |
2a2df321 TZ |
606 | * @glob: The raw string used to register the trigger |
607 | * @cmd: The cmd portion of the string used to register the trigger | |
608 | * @param: The params portion of the string used to register the trigger | |
609 | * | |
610 | * Common implementation for event command parsing and trigger | |
611 | * instantiation. | |
612 | * | |
613 | * Usually used directly as the @func method in event command | |
614 | * implementations. | |
615 | * | |
616 | * Return: 0 on success, errno otherwise | |
617 | */ | |
618 | static int | |
619 | event_trigger_callback(struct event_command *cmd_ops, | |
7f1d2f82 | 620 | struct trace_event_file *file, |
2a2df321 TZ |
621 | char *glob, char *cmd, char *param) |
622 | { | |
623 | struct event_trigger_data *trigger_data; | |
624 | struct event_trigger_ops *trigger_ops; | |
625 | char *trigger = NULL; | |
626 | char *number; | |
627 | int ret; | |
628 | ||
629 | /* separate the trigger from the filter (t:n [if filter]) */ | |
630 | if (param && isdigit(param[0])) | |
631 | trigger = strsep(¶m, " \t"); | |
632 | ||
633 | trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); | |
634 | ||
635 | ret = -ENOMEM; | |
636 | trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); | |
637 | if (!trigger_data) | |
638 | goto out; | |
639 | ||
640 | trigger_data->count = -1; | |
641 | trigger_data->ops = trigger_ops; | |
642 | trigger_data->cmd_ops = cmd_ops; | |
643 | INIT_LIST_HEAD(&trigger_data->list); | |
db1388b4 | 644 | INIT_LIST_HEAD(&trigger_data->named_list); |
2a2df321 TZ |
645 | |
646 | if (glob[0] == '!') { | |
647 | cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); | |
648 | kfree(trigger_data); | |
649 | ret = 0; | |
650 | goto out; | |
651 | } | |
652 | ||
653 | if (trigger) { | |
654 | number = strsep(&trigger, ":"); | |
655 | ||
656 | ret = -EINVAL; | |
657 | if (!strlen(number)) | |
658 | goto out_free; | |
659 | ||
660 | /* | |
661 | * We use the callback data field (which is a pointer) | |
662 | * as our counter. | |
663 | */ | |
664 | ret = kstrtoul(number, 0, &trigger_data->count); | |
665 | if (ret) | |
666 | goto out_free; | |
667 | } | |
668 | ||
669 | if (!param) /* if param is non-empty, it's supposed to be a filter */ | |
670 | goto out_reg; | |
671 | ||
672 | if (!cmd_ops->set_filter) | |
673 | goto out_reg; | |
674 | ||
675 | ret = cmd_ops->set_filter(param, trigger_data, file); | |
676 | if (ret < 0) | |
677 | goto out_free; | |
678 | ||
679 | out_reg: | |
680 | ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); | |
681 | /* | |
682 | * The above returns on success the # of functions enabled, | |
683 | * but if it didn't find any functions it returns zero. | |
684 | * Consider no functions a failure too. | |
685 | */ | |
686 | if (!ret) { | |
687 | ret = -ENOENT; | |
688 | goto out_free; | |
689 | } else if (ret < 0) | |
690 | goto out_free; | |
691 | ret = 0; | |
692 | out: | |
693 | return ret; | |
694 | ||
695 | out_free: | |
bac5fb97 TZ |
696 | if (cmd_ops->set_filter) |
697 | cmd_ops->set_filter(NULL, trigger_data, NULL); | |
2a2df321 TZ |
698 | kfree(trigger_data); |
699 | goto out; | |
700 | } | |
701 | ||
bac5fb97 TZ |
702 | /** |
703 | * set_trigger_filter - Generic event_command @set_filter implementation | |
704 | * @filter_str: The filter string for the trigger, NULL to remove filter | |
705 | * @trigger_data: Trigger-specific data | |
7f1d2f82 | 706 | * @file: The trace_event_file associated with the event |
bac5fb97 TZ |
707 | * |
708 | * Common implementation for event command filter parsing and filter | |
709 | * instantiation. | |
710 | * | |
711 | * Usually used directly as the @set_filter method in event command | |
712 | * implementations. | |
713 | * | |
714 | * Also used to remove a filter (if filter_str = NULL). | |
715 | * | |
716 | * Return: 0 on success, errno otherwise | |
717 | */ | |
ab4bf008 TZ |
718 | int set_trigger_filter(char *filter_str, |
719 | struct event_trigger_data *trigger_data, | |
720 | struct trace_event_file *file) | |
bac5fb97 TZ |
721 | { |
722 | struct event_trigger_data *data = trigger_data; | |
723 | struct event_filter *filter = NULL, *tmp; | |
724 | int ret = -EINVAL; | |
725 | char *s; | |
726 | ||
727 | if (!filter_str) /* clear the current filter */ | |
728 | goto assign; | |
729 | ||
730 | s = strsep(&filter_str, " \t"); | |
731 | ||
732 | if (!strlen(s) || strcmp(s, "if") != 0) | |
733 | goto out; | |
734 | ||
735 | if (!filter_str) | |
736 | goto out; | |
737 | ||
738 | /* The filter is for the 'trigger' event, not the triggered event */ | |
739 | ret = create_event_filter(file->event_call, filter_str, false, &filter); | |
740 | if (ret) | |
741 | goto out; | |
742 | assign: | |
d8a30f20 | 743 | tmp = rcu_access_pointer(data->filter); |
bac5fb97 TZ |
744 | |
745 | rcu_assign_pointer(data->filter, filter); | |
746 | ||
747 | if (tmp) { | |
748 | /* Make sure the call is done with the filter */ | |
749 | synchronize_sched(); | |
750 | free_event_filter(tmp); | |
751 | } | |
752 | ||
753 | kfree(data->filter_str); | |
754 | data->filter_str = NULL; | |
755 | ||
756 | if (filter_str) { | |
757 | data->filter_str = kstrdup(filter_str, GFP_KERNEL); | |
758 | if (!data->filter_str) { | |
d8a30f20 | 759 | free_event_filter(rcu_access_pointer(data->filter)); |
bac5fb97 TZ |
760 | data->filter = NULL; |
761 | ret = -ENOMEM; | |
762 | } | |
763 | } | |
764 | out: | |
765 | return ret; | |
766 | } | |
767 | ||
db1388b4 TZ |
768 | static LIST_HEAD(named_triggers); |
769 | ||
770 | /** | |
771 | * find_named_trigger - Find the common named trigger associated with @name | |
772 | * @name: The name of the set of named triggers to find the common data for | |
773 | * | |
774 | * Named triggers are sets of triggers that share a common set of | |
775 | * trigger data. The first named trigger registered with a given name | |
776 | * owns the common trigger data that the others subsequently | |
777 | * registered with the same name will reference. This function | |
778 | * returns the common trigger data associated with that first | |
779 | * registered instance. | |
780 | * | |
781 | * Return: the common trigger data for the given named trigger on | |
782 | * success, NULL otherwise. | |
783 | */ | |
784 | struct event_trigger_data *find_named_trigger(const char *name) | |
785 | { | |
786 | struct event_trigger_data *data; | |
787 | ||
788 | if (!name) | |
789 | return NULL; | |
790 | ||
791 | list_for_each_entry(data, &named_triggers, named_list) { | |
792 | if (data->named_data) | |
793 | continue; | |
794 | if (strcmp(data->name, name) == 0) | |
795 | return data; | |
796 | } | |
797 | ||
798 | return NULL; | |
799 | } | |
800 | ||
801 | /** | |
802 | * is_named_trigger - determine if a given trigger is a named trigger | |
803 | * @test: The trigger data to test | |
804 | * | |
805 | * Return: true if 'test' is a named trigger, false otherwise. | |
806 | */ | |
807 | bool is_named_trigger(struct event_trigger_data *test) | |
808 | { | |
809 | struct event_trigger_data *data; | |
810 | ||
811 | list_for_each_entry(data, &named_triggers, named_list) { | |
812 | if (test == data) | |
813 | return true; | |
814 | } | |
815 | ||
816 | return false; | |
817 | } | |
818 | ||
819 | /** | |
820 | * save_named_trigger - save the trigger in the named trigger list | |
821 | * @name: The name of the named trigger set | |
822 | * @data: The trigger data to save | |
823 | * | |
824 | * Return: 0 if successful, negative error otherwise. | |
825 | */ | |
826 | int save_named_trigger(const char *name, struct event_trigger_data *data) | |
827 | { | |
828 | data->name = kstrdup(name, GFP_KERNEL); | |
829 | if (!data->name) | |
830 | return -ENOMEM; | |
831 | ||
832 | list_add(&data->named_list, &named_triggers); | |
833 | ||
834 | return 0; | |
835 | } | |
836 | ||
837 | /** | |
838 | * del_named_trigger - delete a trigger from the named trigger list | |
839 | * @data: The trigger data to delete | |
840 | */ | |
841 | void del_named_trigger(struct event_trigger_data *data) | |
842 | { | |
843 | kfree(data->name); | |
844 | data->name = NULL; | |
845 | ||
846 | list_del(&data->named_list); | |
847 | } | |
848 | ||
849 | static void __pause_named_trigger(struct event_trigger_data *data, bool pause) | |
850 | { | |
851 | struct event_trigger_data *test; | |
852 | ||
853 | list_for_each_entry(test, &named_triggers, named_list) { | |
854 | if (strcmp(test->name, data->name) == 0) { | |
855 | if (pause) { | |
856 | test->paused_tmp = test->paused; | |
857 | test->paused = true; | |
858 | } else { | |
859 | test->paused = test->paused_tmp; | |
860 | } | |
861 | } | |
862 | } | |
863 | } | |
864 | ||
865 | /** | |
866 | * pause_named_trigger - Pause all named triggers with the same name | |
867 | * @data: The trigger data of a named trigger to pause | |
868 | * | |
869 | * Pauses a named trigger along with all other triggers having the | |
870 | * same name. Because named triggers share a common set of data, | |
871 | * pausing only one is meaningless, so pausing one named trigger needs | |
872 | * to pause all triggers with the same name. | |
873 | */ | |
874 | void pause_named_trigger(struct event_trigger_data *data) | |
875 | { | |
876 | __pause_named_trigger(data, true); | |
877 | } | |
878 | ||
879 | /** | |
880 | * unpause_named_trigger - Un-pause all named triggers with the same name | |
881 | * @data: The trigger data of a named trigger to unpause | |
882 | * | |
883 | * Un-pauses a named trigger along with all other triggers having the | |
884 | * same name. Because named triggers share a common set of data, | |
885 | * unpausing only one is meaningless, so unpausing one named trigger | |
886 | * needs to unpause all triggers with the same name. | |
887 | */ | |
888 | void unpause_named_trigger(struct event_trigger_data *data) | |
889 | { | |
890 | __pause_named_trigger(data, false); | |
891 | } | |
892 | ||
893 | /** | |
894 | * set_named_trigger_data - Associate common named trigger data | |
895 | * @data: The trigger data of a named trigger to unpause | |
896 | * | |
897 | * Named triggers are sets of triggers that share a common set of | |
898 | * trigger data. The first named trigger registered with a given name | |
899 | * owns the common trigger data that the others subsequently | |
900 | * registered with the same name will reference. This function | |
901 | * associates the common trigger data from the first trigger with the | |
902 | * given trigger. | |
903 | */ | |
904 | void set_named_trigger_data(struct event_trigger_data *data, | |
905 | struct event_trigger_data *named_data) | |
906 | { | |
907 | data->named_data = named_data; | |
908 | } | |
909 | ||
2a2df321 | 910 | static void |
c4a59230 | 911 | traceon_trigger(struct event_trigger_data *data, void *rec) |
2a2df321 TZ |
912 | { |
913 | if (tracing_is_on()) | |
914 | return; | |
915 | ||
916 | tracing_on(); | |
917 | } | |
918 | ||
919 | static void | |
c4a59230 | 920 | traceon_count_trigger(struct event_trigger_data *data, void *rec) |
2a2df321 | 921 | { |
e8dc6371 SRRH |
922 | if (tracing_is_on()) |
923 | return; | |
924 | ||
2a2df321 TZ |
925 | if (!data->count) |
926 | return; | |
927 | ||
928 | if (data->count != -1) | |
929 | (data->count)--; | |
930 | ||
e8dc6371 | 931 | tracing_on(); |
2a2df321 TZ |
932 | } |
933 | ||
934 | static void | |
c4a59230 | 935 | traceoff_trigger(struct event_trigger_data *data, void *rec) |
2a2df321 TZ |
936 | { |
937 | if (!tracing_is_on()) | |
938 | return; | |
939 | ||
940 | tracing_off(); | |
941 | } | |
942 | ||
943 | static void | |
c4a59230 | 944 | traceoff_count_trigger(struct event_trigger_data *data, void *rec) |
2a2df321 | 945 | { |
e8dc6371 SRRH |
946 | if (!tracing_is_on()) |
947 | return; | |
948 | ||
2a2df321 TZ |
949 | if (!data->count) |
950 | return; | |
951 | ||
952 | if (data->count != -1) | |
953 | (data->count)--; | |
954 | ||
e8dc6371 | 955 | tracing_off(); |
2a2df321 TZ |
956 | } |
957 | ||
958 | static int | |
959 | traceon_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
960 | struct event_trigger_data *data) | |
961 | { | |
962 | return event_trigger_print("traceon", m, (void *)data->count, | |
963 | data->filter_str); | |
964 | } | |
965 | ||
966 | static int | |
967 | traceoff_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
968 | struct event_trigger_data *data) | |
969 | { | |
970 | return event_trigger_print("traceoff", m, (void *)data->count, | |
971 | data->filter_str); | |
972 | } | |
973 | ||
974 | static struct event_trigger_ops traceon_trigger_ops = { | |
975 | .func = traceon_trigger, | |
976 | .print = traceon_trigger_print, | |
977 | .init = event_trigger_init, | |
978 | .free = event_trigger_free, | |
979 | }; | |
980 | ||
981 | static struct event_trigger_ops traceon_count_trigger_ops = { | |
982 | .func = traceon_count_trigger, | |
983 | .print = traceon_trigger_print, | |
984 | .init = event_trigger_init, | |
985 | .free = event_trigger_free, | |
986 | }; | |
987 | ||
988 | static struct event_trigger_ops traceoff_trigger_ops = { | |
989 | .func = traceoff_trigger, | |
990 | .print = traceoff_trigger_print, | |
991 | .init = event_trigger_init, | |
992 | .free = event_trigger_free, | |
993 | }; | |
994 | ||
995 | static struct event_trigger_ops traceoff_count_trigger_ops = { | |
996 | .func = traceoff_count_trigger, | |
997 | .print = traceoff_trigger_print, | |
998 | .init = event_trigger_init, | |
999 | .free = event_trigger_free, | |
1000 | }; | |
1001 | ||
1002 | static struct event_trigger_ops * | |
1003 | onoff_get_trigger_ops(char *cmd, char *param) | |
1004 | { | |
1005 | struct event_trigger_ops *ops; | |
1006 | ||
1007 | /* we register both traceon and traceoff to this callback */ | |
1008 | if (strcmp(cmd, "traceon") == 0) | |
1009 | ops = param ? &traceon_count_trigger_ops : | |
1010 | &traceon_trigger_ops; | |
1011 | else | |
1012 | ops = param ? &traceoff_count_trigger_ops : | |
1013 | &traceoff_trigger_ops; | |
1014 | ||
1015 | return ops; | |
1016 | } | |
1017 | ||
1018 | static struct event_command trigger_traceon_cmd = { | |
1019 | .name = "traceon", | |
1020 | .trigger_type = ETT_TRACE_ONOFF, | |
1021 | .func = event_trigger_callback, | |
1022 | .reg = register_trigger, | |
1023 | .unreg = unregister_trigger, | |
1024 | .get_trigger_ops = onoff_get_trigger_ops, | |
bac5fb97 | 1025 | .set_filter = set_trigger_filter, |
2a2df321 TZ |
1026 | }; |
1027 | ||
1028 | static struct event_command trigger_traceoff_cmd = { | |
1029 | .name = "traceoff", | |
1030 | .trigger_type = ETT_TRACE_ONOFF, | |
a0d0c621 | 1031 | .flags = EVENT_CMD_FL_POST_TRIGGER, |
2a2df321 TZ |
1032 | .func = event_trigger_callback, |
1033 | .reg = register_trigger, | |
1034 | .unreg = unregister_trigger, | |
1035 | .get_trigger_ops = onoff_get_trigger_ops, | |
bac5fb97 | 1036 | .set_filter = set_trigger_filter, |
2a2df321 TZ |
1037 | }; |
1038 | ||
93e31ffb TZ |
1039 | #ifdef CONFIG_TRACER_SNAPSHOT |
1040 | static void | |
c4a59230 | 1041 | snapshot_trigger(struct event_trigger_data *data, void *rec) |
93e31ffb TZ |
1042 | { |
1043 | tracing_snapshot(); | |
1044 | } | |
1045 | ||
1046 | static void | |
c4a59230 | 1047 | snapshot_count_trigger(struct event_trigger_data *data, void *rec) |
93e31ffb TZ |
1048 | { |
1049 | if (!data->count) | |
1050 | return; | |
1051 | ||
1052 | if (data->count != -1) | |
1053 | (data->count)--; | |
1054 | ||
c4a59230 | 1055 | snapshot_trigger(data, rec); |
93e31ffb TZ |
1056 | } |
1057 | ||
1058 | static int | |
1059 | register_snapshot_trigger(char *glob, struct event_trigger_ops *ops, | |
1060 | struct event_trigger_data *data, | |
7f1d2f82 | 1061 | struct trace_event_file *file) |
93e31ffb TZ |
1062 | { |
1063 | int ret = register_trigger(glob, ops, data, file); | |
1064 | ||
1065 | if (ret > 0 && tracing_alloc_snapshot() != 0) { | |
1066 | unregister_trigger(glob, ops, data, file); | |
1067 | ret = 0; | |
1068 | } | |
1069 | ||
1070 | return ret; | |
1071 | } | |
1072 | ||
1073 | static int | |
1074 | snapshot_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
1075 | struct event_trigger_data *data) | |
1076 | { | |
1077 | return event_trigger_print("snapshot", m, (void *)data->count, | |
1078 | data->filter_str); | |
1079 | } | |
1080 | ||
1081 | static struct event_trigger_ops snapshot_trigger_ops = { | |
1082 | .func = snapshot_trigger, | |
1083 | .print = snapshot_trigger_print, | |
1084 | .init = event_trigger_init, | |
1085 | .free = event_trigger_free, | |
1086 | }; | |
1087 | ||
1088 | static struct event_trigger_ops snapshot_count_trigger_ops = { | |
1089 | .func = snapshot_count_trigger, | |
1090 | .print = snapshot_trigger_print, | |
1091 | .init = event_trigger_init, | |
1092 | .free = event_trigger_free, | |
1093 | }; | |
1094 | ||
1095 | static struct event_trigger_ops * | |
1096 | snapshot_get_trigger_ops(char *cmd, char *param) | |
1097 | { | |
1098 | return param ? &snapshot_count_trigger_ops : &snapshot_trigger_ops; | |
1099 | } | |
1100 | ||
1101 | static struct event_command trigger_snapshot_cmd = { | |
1102 | .name = "snapshot", | |
1103 | .trigger_type = ETT_SNAPSHOT, | |
1104 | .func = event_trigger_callback, | |
1105 | .reg = register_snapshot_trigger, | |
1106 | .unreg = unregister_trigger, | |
1107 | .get_trigger_ops = snapshot_get_trigger_ops, | |
bac5fb97 | 1108 | .set_filter = set_trigger_filter, |
93e31ffb TZ |
1109 | }; |
1110 | ||
1111 | static __init int register_trigger_snapshot_cmd(void) | |
1112 | { | |
1113 | int ret; | |
1114 | ||
1115 | ret = register_event_command(&trigger_snapshot_cmd); | |
1116 | WARN_ON(ret < 0); | |
1117 | ||
1118 | return ret; | |
1119 | } | |
1120 | #else | |
1121 | static __init int register_trigger_snapshot_cmd(void) { return 0; } | |
1122 | #endif /* CONFIG_TRACER_SNAPSHOT */ | |
1123 | ||
f21ecbb3 TZ |
1124 | #ifdef CONFIG_STACKTRACE |
1125 | /* | |
1126 | * Skip 3: | |
1127 | * stacktrace_trigger() | |
1128 | * event_triggers_post_call() | |
a7237765 | 1129 | * trace_event_raw_event_xxx() |
f21ecbb3 TZ |
1130 | */ |
1131 | #define STACK_SKIP 3 | |
1132 | ||
1133 | static void | |
c4a59230 | 1134 | stacktrace_trigger(struct event_trigger_data *data, void *rec) |
f21ecbb3 TZ |
1135 | { |
1136 | trace_dump_stack(STACK_SKIP); | |
1137 | } | |
1138 | ||
1139 | static void | |
c4a59230 | 1140 | stacktrace_count_trigger(struct event_trigger_data *data, void *rec) |
f21ecbb3 TZ |
1141 | { |
1142 | if (!data->count) | |
1143 | return; | |
1144 | ||
1145 | if (data->count != -1) | |
1146 | (data->count)--; | |
1147 | ||
c4a59230 | 1148 | stacktrace_trigger(data, rec); |
f21ecbb3 TZ |
1149 | } |
1150 | ||
1151 | static int | |
1152 | stacktrace_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
1153 | struct event_trigger_data *data) | |
1154 | { | |
1155 | return event_trigger_print("stacktrace", m, (void *)data->count, | |
1156 | data->filter_str); | |
1157 | } | |
1158 | ||
1159 | static struct event_trigger_ops stacktrace_trigger_ops = { | |
1160 | .func = stacktrace_trigger, | |
1161 | .print = stacktrace_trigger_print, | |
1162 | .init = event_trigger_init, | |
1163 | .free = event_trigger_free, | |
1164 | }; | |
1165 | ||
1166 | static struct event_trigger_ops stacktrace_count_trigger_ops = { | |
1167 | .func = stacktrace_count_trigger, | |
1168 | .print = stacktrace_trigger_print, | |
1169 | .init = event_trigger_init, | |
1170 | .free = event_trigger_free, | |
1171 | }; | |
1172 | ||
1173 | static struct event_trigger_ops * | |
1174 | stacktrace_get_trigger_ops(char *cmd, char *param) | |
1175 | { | |
1176 | return param ? &stacktrace_count_trigger_ops : &stacktrace_trigger_ops; | |
1177 | } | |
1178 | ||
1179 | static struct event_command trigger_stacktrace_cmd = { | |
1180 | .name = "stacktrace", | |
1181 | .trigger_type = ETT_STACKTRACE, | |
353206f5 | 1182 | .flags = EVENT_CMD_FL_POST_TRIGGER, |
f21ecbb3 TZ |
1183 | .func = event_trigger_callback, |
1184 | .reg = register_trigger, | |
1185 | .unreg = unregister_trigger, | |
1186 | .get_trigger_ops = stacktrace_get_trigger_ops, | |
bac5fb97 | 1187 | .set_filter = set_trigger_filter, |
f21ecbb3 TZ |
1188 | }; |
1189 | ||
1190 | static __init int register_trigger_stacktrace_cmd(void) | |
1191 | { | |
1192 | int ret; | |
1193 | ||
1194 | ret = register_event_command(&trigger_stacktrace_cmd); | |
1195 | WARN_ON(ret < 0); | |
1196 | ||
1197 | return ret; | |
1198 | } | |
1199 | #else | |
1200 | static __init int register_trigger_stacktrace_cmd(void) { return 0; } | |
1201 | #endif /* CONFIG_STACKTRACE */ | |
1202 | ||
2a2df321 TZ |
1203 | static __init void unregister_trigger_traceon_traceoff_cmds(void) |
1204 | { | |
1205 | unregister_event_command(&trigger_traceon_cmd); | |
1206 | unregister_event_command(&trigger_traceoff_cmd); | |
1207 | } | |
1208 | ||
7862ad18 | 1209 | static void |
c4a59230 | 1210 | event_enable_trigger(struct event_trigger_data *data, void *rec) |
7862ad18 TZ |
1211 | { |
1212 | struct enable_trigger_data *enable_data = data->private_data; | |
1213 | ||
1214 | if (enable_data->enable) | |
5d6ad960 | 1215 | clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); |
7862ad18 | 1216 | else |
5d6ad960 | 1217 | set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); |
7862ad18 TZ |
1218 | } |
1219 | ||
1220 | static void | |
c4a59230 | 1221 | event_enable_count_trigger(struct event_trigger_data *data, void *rec) |
7862ad18 TZ |
1222 | { |
1223 | struct enable_trigger_data *enable_data = data->private_data; | |
1224 | ||
1225 | if (!data->count) | |
1226 | return; | |
1227 | ||
1228 | /* Skip if the event is in a state we want to switch to */ | |
5d6ad960 | 1229 | if (enable_data->enable == !(enable_data->file->flags & EVENT_FILE_FL_SOFT_DISABLED)) |
7862ad18 TZ |
1230 | return; |
1231 | ||
1232 | if (data->count != -1) | |
1233 | (data->count)--; | |
1234 | ||
c4a59230 | 1235 | event_enable_trigger(data, rec); |
7862ad18 TZ |
1236 | } |
1237 | ||
d0bad49b TZ |
1238 | int event_enable_trigger_print(struct seq_file *m, |
1239 | struct event_trigger_ops *ops, | |
1240 | struct event_trigger_data *data) | |
7862ad18 TZ |
1241 | { |
1242 | struct enable_trigger_data *enable_data = data->private_data; | |
1243 | ||
1244 | seq_printf(m, "%s:%s:%s", | |
d0bad49b TZ |
1245 | enable_data->hist ? |
1246 | (enable_data->enable ? ENABLE_HIST_STR : DISABLE_HIST_STR) : | |
1247 | (enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR), | |
7862ad18 | 1248 | enable_data->file->event_call->class->system, |
687fcc4a | 1249 | trace_event_name(enable_data->file->event_call)); |
7862ad18 TZ |
1250 | |
1251 | if (data->count == -1) | |
1252 | seq_puts(m, ":unlimited"); | |
1253 | else | |
1254 | seq_printf(m, ":count=%ld", data->count); | |
1255 | ||
1256 | if (data->filter_str) | |
1257 | seq_printf(m, " if %s\n", data->filter_str); | |
1258 | else | |
1177e436 | 1259 | seq_putc(m, '\n'); |
7862ad18 TZ |
1260 | |
1261 | return 0; | |
1262 | } | |
1263 | ||
d0bad49b TZ |
1264 | void event_enable_trigger_free(struct event_trigger_ops *ops, |
1265 | struct event_trigger_data *data) | |
7862ad18 TZ |
1266 | { |
1267 | struct enable_trigger_data *enable_data = data->private_data; | |
1268 | ||
1269 | if (WARN_ON_ONCE(data->ref <= 0)) | |
1270 | return; | |
1271 | ||
1272 | data->ref--; | |
1273 | if (!data->ref) { | |
1274 | /* Remove the SOFT_MODE flag */ | |
1275 | trace_event_enable_disable(enable_data->file, 0, 1); | |
1276 | module_put(enable_data->file->event_call->mod); | |
1277 | trigger_data_free(data); | |
1278 | kfree(enable_data); | |
1279 | } | |
1280 | } | |
1281 | ||
1282 | static struct event_trigger_ops event_enable_trigger_ops = { | |
1283 | .func = event_enable_trigger, | |
1284 | .print = event_enable_trigger_print, | |
1285 | .init = event_trigger_init, | |
1286 | .free = event_enable_trigger_free, | |
1287 | }; | |
1288 | ||
1289 | static struct event_trigger_ops event_enable_count_trigger_ops = { | |
1290 | .func = event_enable_count_trigger, | |
1291 | .print = event_enable_trigger_print, | |
1292 | .init = event_trigger_init, | |
1293 | .free = event_enable_trigger_free, | |
1294 | }; | |
1295 | ||
1296 | static struct event_trigger_ops event_disable_trigger_ops = { | |
1297 | .func = event_enable_trigger, | |
1298 | .print = event_enable_trigger_print, | |
1299 | .init = event_trigger_init, | |
1300 | .free = event_enable_trigger_free, | |
1301 | }; | |
1302 | ||
1303 | static struct event_trigger_ops event_disable_count_trigger_ops = { | |
1304 | .func = event_enable_count_trigger, | |
1305 | .print = event_enable_trigger_print, | |
1306 | .init = event_trigger_init, | |
1307 | .free = event_enable_trigger_free, | |
1308 | }; | |
1309 | ||
d0bad49b TZ |
1310 | int event_enable_trigger_func(struct event_command *cmd_ops, |
1311 | struct trace_event_file *file, | |
1312 | char *glob, char *cmd, char *param) | |
7862ad18 | 1313 | { |
7f1d2f82 | 1314 | struct trace_event_file *event_enable_file; |
7862ad18 TZ |
1315 | struct enable_trigger_data *enable_data; |
1316 | struct event_trigger_data *trigger_data; | |
1317 | struct event_trigger_ops *trigger_ops; | |
1318 | struct trace_array *tr = file->tr; | |
1319 | const char *system; | |
1320 | const char *event; | |
d0bad49b | 1321 | bool hist = false; |
7862ad18 TZ |
1322 | char *trigger; |
1323 | char *number; | |
1324 | bool enable; | |
1325 | int ret; | |
1326 | ||
1327 | if (!param) | |
1328 | return -EINVAL; | |
1329 | ||
1330 | /* separate the trigger from the filter (s:e:n [if filter]) */ | |
1331 | trigger = strsep(¶m, " \t"); | |
1332 | if (!trigger) | |
1333 | return -EINVAL; | |
1334 | ||
1335 | system = strsep(&trigger, ":"); | |
1336 | if (!trigger) | |
1337 | return -EINVAL; | |
1338 | ||
1339 | event = strsep(&trigger, ":"); | |
1340 | ||
1341 | ret = -EINVAL; | |
1342 | event_enable_file = find_event_file(tr, system, event); | |
1343 | if (!event_enable_file) | |
1344 | goto out; | |
1345 | ||
d0bad49b TZ |
1346 | #ifdef CONFIG_HIST_TRIGGERS |
1347 | hist = ((strcmp(cmd, ENABLE_HIST_STR) == 0) || | |
1348 | (strcmp(cmd, DISABLE_HIST_STR) == 0)); | |
7862ad18 | 1349 | |
d0bad49b TZ |
1350 | enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) || |
1351 | (strcmp(cmd, ENABLE_HIST_STR) == 0)); | |
1352 | #else | |
1353 | enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; | |
1354 | #endif | |
7862ad18 TZ |
1355 | trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); |
1356 | ||
1357 | ret = -ENOMEM; | |
1358 | trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); | |
1359 | if (!trigger_data) | |
1360 | goto out; | |
1361 | ||
1362 | enable_data = kzalloc(sizeof(*enable_data), GFP_KERNEL); | |
1363 | if (!enable_data) { | |
1364 | kfree(trigger_data); | |
1365 | goto out; | |
1366 | } | |
1367 | ||
1368 | trigger_data->count = -1; | |
1369 | trigger_data->ops = trigger_ops; | |
1370 | trigger_data->cmd_ops = cmd_ops; | |
1371 | INIT_LIST_HEAD(&trigger_data->list); | |
1372 | RCU_INIT_POINTER(trigger_data->filter, NULL); | |
1373 | ||
d0bad49b | 1374 | enable_data->hist = hist; |
7862ad18 TZ |
1375 | enable_data->enable = enable; |
1376 | enable_data->file = event_enable_file; | |
1377 | trigger_data->private_data = enable_data; | |
1378 | ||
1379 | if (glob[0] == '!') { | |
1380 | cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); | |
1381 | kfree(trigger_data); | |
1382 | kfree(enable_data); | |
1383 | ret = 0; | |
1384 | goto out; | |
1385 | } | |
1386 | ||
1387 | if (trigger) { | |
1388 | number = strsep(&trigger, ":"); | |
1389 | ||
1390 | ret = -EINVAL; | |
1391 | if (!strlen(number)) | |
1392 | goto out_free; | |
1393 | ||
1394 | /* | |
1395 | * We use the callback data field (which is a pointer) | |
1396 | * as our counter. | |
1397 | */ | |
1398 | ret = kstrtoul(number, 0, &trigger_data->count); | |
1399 | if (ret) | |
1400 | goto out_free; | |
1401 | } | |
1402 | ||
1403 | if (!param) /* if param is non-empty, it's supposed to be a filter */ | |
1404 | goto out_reg; | |
1405 | ||
1406 | if (!cmd_ops->set_filter) | |
1407 | goto out_reg; | |
1408 | ||
1409 | ret = cmd_ops->set_filter(param, trigger_data, file); | |
1410 | if (ret < 0) | |
1411 | goto out_free; | |
1412 | ||
1413 | out_reg: | |
1414 | /* Don't let event modules unload while probe registered */ | |
1415 | ret = try_module_get(event_enable_file->event_call->mod); | |
1416 | if (!ret) { | |
1417 | ret = -EBUSY; | |
1418 | goto out_free; | |
1419 | } | |
1420 | ||
1421 | ret = trace_event_enable_disable(event_enable_file, 1, 1); | |
1422 | if (ret < 0) | |
1423 | goto out_put; | |
1424 | ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); | |
1425 | /* | |
1426 | * The above returns on success the # of functions enabled, | |
1427 | * but if it didn't find any functions it returns zero. | |
1428 | * Consider no functions a failure too. | |
1429 | */ | |
1430 | if (!ret) { | |
1431 | ret = -ENOENT; | |
1432 | goto out_disable; | |
1433 | } else if (ret < 0) | |
1434 | goto out_disable; | |
1435 | /* Just return zero, not the number of enabled functions */ | |
1436 | ret = 0; | |
1437 | out: | |
1438 | return ret; | |
1439 | ||
1440 | out_disable: | |
1441 | trace_event_enable_disable(event_enable_file, 0, 1); | |
1442 | out_put: | |
1443 | module_put(event_enable_file->event_call->mod); | |
1444 | out_free: | |
bac5fb97 TZ |
1445 | if (cmd_ops->set_filter) |
1446 | cmd_ops->set_filter(NULL, trigger_data, NULL); | |
7862ad18 TZ |
1447 | kfree(trigger_data); |
1448 | kfree(enable_data); | |
1449 | goto out; | |
1450 | } | |
1451 | ||
d0bad49b TZ |
1452 | int event_enable_register_trigger(char *glob, |
1453 | struct event_trigger_ops *ops, | |
1454 | struct event_trigger_data *data, | |
1455 | struct trace_event_file *file) | |
7862ad18 TZ |
1456 | { |
1457 | struct enable_trigger_data *enable_data = data->private_data; | |
1458 | struct enable_trigger_data *test_enable_data; | |
1459 | struct event_trigger_data *test; | |
1460 | int ret = 0; | |
1461 | ||
1462 | list_for_each_entry_rcu(test, &file->triggers, list) { | |
1463 | test_enable_data = test->private_data; | |
1464 | if (test_enable_data && | |
d0bad49b TZ |
1465 | (test->cmd_ops->trigger_type == |
1466 | data->cmd_ops->trigger_type) && | |
7862ad18 TZ |
1467 | (test_enable_data->file == enable_data->file)) { |
1468 | ret = -EEXIST; | |
1469 | goto out; | |
1470 | } | |
1471 | } | |
1472 | ||
1473 | if (data->ops->init) { | |
1474 | ret = data->ops->init(data->ops, data); | |
1475 | if (ret < 0) | |
1476 | goto out; | |
1477 | } | |
1478 | ||
1479 | list_add_rcu(&data->list, &file->triggers); | |
1480 | ret++; | |
1481 | ||
4e4a4d75 | 1482 | update_cond_flag(file); |
7862ad18 TZ |
1483 | if (trace_event_trigger_enable_disable(file, 1) < 0) { |
1484 | list_del_rcu(&data->list); | |
4e4a4d75 | 1485 | update_cond_flag(file); |
7862ad18 TZ |
1486 | ret--; |
1487 | } | |
1488 | out: | |
1489 | return ret; | |
1490 | } | |
1491 | ||
d0bad49b TZ |
1492 | void event_enable_unregister_trigger(char *glob, |
1493 | struct event_trigger_ops *ops, | |
1494 | struct event_trigger_data *test, | |
1495 | struct trace_event_file *file) | |
7862ad18 TZ |
1496 | { |
1497 | struct enable_trigger_data *test_enable_data = test->private_data; | |
1498 | struct enable_trigger_data *enable_data; | |
1499 | struct event_trigger_data *data; | |
1500 | bool unregistered = false; | |
1501 | ||
1502 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
1503 | enable_data = data->private_data; | |
1504 | if (enable_data && | |
d0bad49b TZ |
1505 | (data->cmd_ops->trigger_type == |
1506 | test->cmd_ops->trigger_type) && | |
7862ad18 TZ |
1507 | (enable_data->file == test_enable_data->file)) { |
1508 | unregistered = true; | |
1509 | list_del_rcu(&data->list); | |
1510 | trace_event_trigger_enable_disable(file, 0); | |
4e4a4d75 | 1511 | update_cond_flag(file); |
7862ad18 TZ |
1512 | break; |
1513 | } | |
1514 | } | |
1515 | ||
1516 | if (unregistered && data->ops->free) | |
1517 | data->ops->free(data->ops, data); | |
1518 | } | |
1519 | ||
1520 | static struct event_trigger_ops * | |
1521 | event_enable_get_trigger_ops(char *cmd, char *param) | |
1522 | { | |
1523 | struct event_trigger_ops *ops; | |
1524 | bool enable; | |
1525 | ||
d0bad49b TZ |
1526 | #ifdef CONFIG_HIST_TRIGGERS |
1527 | enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) || | |
1528 | (strcmp(cmd, ENABLE_HIST_STR) == 0)); | |
1529 | #else | |
7862ad18 | 1530 | enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; |
d0bad49b | 1531 | #endif |
7862ad18 TZ |
1532 | if (enable) |
1533 | ops = param ? &event_enable_count_trigger_ops : | |
1534 | &event_enable_trigger_ops; | |
1535 | else | |
1536 | ops = param ? &event_disable_count_trigger_ops : | |
1537 | &event_disable_trigger_ops; | |
1538 | ||
1539 | return ops; | |
1540 | } | |
1541 | ||
1542 | static struct event_command trigger_enable_cmd = { | |
1543 | .name = ENABLE_EVENT_STR, | |
1544 | .trigger_type = ETT_EVENT_ENABLE, | |
1545 | .func = event_enable_trigger_func, | |
1546 | .reg = event_enable_register_trigger, | |
1547 | .unreg = event_enable_unregister_trigger, | |
1548 | .get_trigger_ops = event_enable_get_trigger_ops, | |
bac5fb97 | 1549 | .set_filter = set_trigger_filter, |
7862ad18 TZ |
1550 | }; |
1551 | ||
1552 | static struct event_command trigger_disable_cmd = { | |
1553 | .name = DISABLE_EVENT_STR, | |
1554 | .trigger_type = ETT_EVENT_ENABLE, | |
1555 | .func = event_enable_trigger_func, | |
1556 | .reg = event_enable_register_trigger, | |
1557 | .unreg = event_enable_unregister_trigger, | |
1558 | .get_trigger_ops = event_enable_get_trigger_ops, | |
bac5fb97 | 1559 | .set_filter = set_trigger_filter, |
7862ad18 TZ |
1560 | }; |
1561 | ||
1562 | static __init void unregister_trigger_enable_disable_cmds(void) | |
1563 | { | |
1564 | unregister_event_command(&trigger_enable_cmd); | |
1565 | unregister_event_command(&trigger_disable_cmd); | |
1566 | } | |
1567 | ||
1568 | static __init int register_trigger_enable_disable_cmds(void) | |
1569 | { | |
1570 | int ret; | |
1571 | ||
1572 | ret = register_event_command(&trigger_enable_cmd); | |
1573 | if (WARN_ON(ret < 0)) | |
1574 | return ret; | |
1575 | ret = register_event_command(&trigger_disable_cmd); | |
1576 | if (WARN_ON(ret < 0)) | |
1577 | unregister_trigger_enable_disable_cmds(); | |
1578 | ||
1579 | return ret; | |
1580 | } | |
1581 | ||
2a2df321 TZ |
1582 | static __init int register_trigger_traceon_traceoff_cmds(void) |
1583 | { | |
1584 | int ret; | |
1585 | ||
1586 | ret = register_event_command(&trigger_traceon_cmd); | |
1587 | if (WARN_ON(ret < 0)) | |
1588 | return ret; | |
1589 | ret = register_event_command(&trigger_traceoff_cmd); | |
1590 | if (WARN_ON(ret < 0)) | |
1591 | unregister_trigger_traceon_traceoff_cmds(); | |
1592 | ||
1593 | return ret; | |
1594 | } | |
1595 | ||
85f2b082 TZ |
1596 | __init int register_trigger_cmds(void) |
1597 | { | |
2a2df321 | 1598 | register_trigger_traceon_traceoff_cmds(); |
93e31ffb | 1599 | register_trigger_snapshot_cmd(); |
f21ecbb3 | 1600 | register_trigger_stacktrace_cmd(); |
7862ad18 | 1601 | register_trigger_enable_disable_cmds(); |
d0bad49b | 1602 | register_trigger_hist_enable_disable_cmds(); |
7ef224d1 | 1603 | register_trigger_hist_cmd(); |
2a2df321 | 1604 | |
85f2b082 TZ |
1605 | return 0; |
1606 | } |